This book is dedicated to the persistent crucial issues of child marriage and adolescent childbearing in developing countries. The first chapter summarizes the main articles from different treaties and conventions dealing with the Rights of the Child and adopted at international, regional and national levels. The second and the third chapters analyse disaggregated data provided by UNICEF-MICS surveys on child marriage and by USAID-DHS surveys on adolescent childbearing in a large number of countries across the world. The prevalence of child marriage and teenage childbearing show huge gaps between and within countries across the world. In the quasi totality of countries considered, poor, rural and uneducated girls are much more likely to be married and to be pregnant before age 18 than their advantaged counterparts (rich, urban and highly educated girls). This book offers a pragmatic plate-form for readers of different levels and status, including academic staff, researchers, PhD students, decision makers and members of civil society concerned by the Rights of the Child in general and by early marriage and adolescent pregnancy and motherhood in particular.